Induction meter



A. CALLSEN INDUCTION METER Dec. 30, 1930.

Filed Aug. 30. 1928 INVENTOR Alba/'7 Cal/sen BY M A a-4W ATTORNEY Patented Dec. 30, .1930 .15;

UNITED STATES PATENT oFFice ALBERT CALLSEN, 0F NUREMBERG, GERMANY, ASSIGNOE TO WESTIN HOUSE ELECTRIC & MANUFACTURING CGMPANY, A CORPORATION OF PENNSYLVANIA INDUCTION METER Application filed August 30, 1928, Serial No. 303,013, and in Germany Auguste, 1927.

My invention relates to induction meters and more particularly to means for improving the operation of induction meters upon changes of temperature.

My invention has for an object to provide means for compensating induction watthour meters for errors incident to temperature changes.

In my British Patent No. 277,015 dated May 2st, 1928, I describe and claim means for compensating an induction watthour meter for temperature errors including a thermal alloy having a high negative temperature coefficient of permeability disposed in one of the driving flux paths.

Figs. 1 and 2 of the above-mentioned patent illustrate how the thermal alloy members may be mounted on the voltage magnet so that they are in the path of the current driving flux.

My invention provides means for simply and eiiiciently accomplishing the same result with a small amount of material by mounting the thermal alloy directly on the voltage magnet by means of screws. The thermal alloy members are each angular in form so that one limb may be secured to the voltage magnet and the other limb extend into the air gap,

containing the armature disc, in the path of the flux from the current magnet.

This arrangement is diagrammatically illust-rated in the drawing afliXed hereto and forming part of my specification.

The drawing shows a perspective view of the two driving magnets located at an enlarged distance apart for the purpose of disclosing the lower portions of the voltage magnet.

The voltage magnet S, with the potential winding 8, consists of a U-shaped core provided with limbs S and S having a yoke S and a central member S upon which the potential coil 8 is mounted. The two core limbs of the voltage magnet are held together by means of a brass bar m, which is attached to the core limbs S and S by screws a and a respectively, and to the central member S by a screw (4 The upper end of the member S fits into a recess of the yoke S that is covered by plates .72 and Z2 A contact clip R is also secured to the vol"- age magnet S by the screws a and a and a tongue *0 on said clip passes around the edge of the armature disc A and constitutes, together with the slightly projecting pole of the core 3,, an air gap L for the potential driving flux.

A main current magnet H, provided with a winding h, is so disposed, in'the assembled driving system, that the pole portions thereof are adjacent to the potential magnet, as indicated in broken lines at H and H Thermal alloy elements YV and V7 having a negative temperature coeflicient of permeability, are preferably angular having one limb thereof secured to the voltage magnet by means of the screws a and a and the free lin i b thereof located in the air gap, as shown.

ine thermal alloy angles WV, and WV may be readily mounted on the shunt pole portions of standard existing watthour meters without altering their structure, thereby providing ready means for immediately improving the operation of present meters without the necessity of redesigning them.

Various changes and modifications may be made without departing from the spirit of my invention and the appended claims and I desire therefore, that only such restrictions be placed upon them as are imposed by the prior art.

I claim as my invention:

1. The combination with an induction meter including relatively movable magneticfluX co-acting members disposed in slightlyspaced substantially parallel surface-to-surface relation to provide a narrow air gap therebetween, of a temperaturecompensating element embodying a magnetic portion in said gap, and supporting means therefor exterior to the gap.

2. The combination with an induction me; ter including a disk armature, and means for actuating the armature including a magnet element having a pole-end surface in slightly-spaced substantially parallel surface-to-surface relation to the armature to therewith provide a narrow air gap, of temperature-compensating means embodying a magnetic portion in said gap, and supporting means therefor mounted on said magnet element exterior to the gap.

3. The combination with an induction meter including a disk armature and means for actuating the armature including a magnet element having a pole-end surface in slightly-spaced substantially parallel surface-tosurface relation to the armature to therewith provide a narrow air gap, of temperature Compensating means embodying a magnetic member having angularly related portions, one of which is disposed in said gap and one of which is removably mounted on said magnet element exterior to the gap.

In testimony whereof, I have hereunto subscribed my name this 17th day of July,

ALBERT OALLSEN. 

